Synthesis and Characterization of PSLZT-BMT-PMS-Based Hard Piezoelectric Ceramics for Piezoelectric Ring Applications in Power Ultrasonic Transducers

Hard piezoelectric ceramics with the composition 0.97[(~Pb<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.94</inf> Sr<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.05</inf> La<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.01</inf>)(Zr<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.51</inf> Ti<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.49</inf>) O<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf>]-0.024[Bi(Mn<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1/2</inf> Ti<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1/2</inf>) O<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf>] -0.006[~Pb(Mn<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</inf>/<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> Sb<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf>/<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf>) O<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf>] (abbreviated as PSLZT-BMT-PMS) doped with y wt.% Fe<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf>O<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf>(y=0.0-0.6) were successfully synthesized via the traditional solid-state reaction technique. The aim of this study is to develop hard piezoelectric ceramics with a high mechanical quality factor (Qm) by investigating the effects of Fe<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf>O<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> doping on phase structural transformation and electromechanical properties. Experimental results indicate that the composition with 0.3 wt.% Fe<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf>O<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> exhibits superior properties with Qm=2009, tanδ=0.003, ~d 33=425 pC/N,kp = 0.60, Pr=26.0μ C/cm2, and Ec = 6.8 kV/cm. These enhanced properties are attributed to phase structure transitions that form morphotropic phase boundaries, optimized microstructural characteristics, and reduced dielectric losses. Furthermore, the finite element method (FEM) was employed to model and analyze the resonance behavior of piezoelectric rings (50 mm outer diameter, 5 mm thickness) designed for high-power ultrasonic transducers. The optimized ceramic composition was used to fabricate actual piezoelectric rings via the solid-state reaction process, and their resonance characteristics were experimentally measured and compared with simulation results. The rings demonstrated resonance and anti-resonance frequencies around 32.2 kHz and 36.2 kHz, respectively, confirming their suitability for high-power piezoelectric applications.